Among the differences between automatic firearms and semi-automatic firearms is the rate of their respective firing cycles. Generally, the firing cycle of a semi-automatic firearm involves the sequential steps of depressing the trigger, releasing the trigger, and re-depressing the trigger. Upon discharge, a semi-automatic firearm typically ejects a spent cartridge casing and sequentially feeds a loaded cartridge into the chamber. The “auto-loading” feature of the semi-automatic does not change the fact that a semi-automatic firearm will not discharge without the sequential release and re-depression of the trigger. Hence, the rate of the firing cycle of these firearms is limited by the speed at which the shooter can repeatedly depress, release, and re-depress the trigger.
The firing rate of an automatic firearm, on the other hand, is not. Instead, an automatic firearm will continue to rapidly fire all available rounds in the magazine so long as the trigger remains depressed. When the rate of the firing cycle of the automatic is compared to the firing rate of the semi-automatic, one understands that the firing rate of the semi-automatic firearm is typically limited by the shooter's reaction time; and, even the most proficient shooter cannot discharge more than about one or two rounds per second.
It is important to understand that the National Firearms Act prohibits possession of automatic firearms within the United States, or the District of Columbia, without special authorization. As a result, some innovators have tried to enhance the cyclic firing rate of a semi-automatic firearm to approach the firing rate of the automatic.
Such devices and methods, however, are replete with shortcomings. One such method, like the apparatus shown in U.S. Pat. No. 6,101,918, requires substantial irrevocable modifications to the firearm. The stock is cut out, and a stop member is permanently secured to the stock near the trigger assembly, for example. U.S. Pat. No. 5,074,190 describes another device that has a spring-biased paddle that engages the rear of the trigger and continually urges it forwardly. This device, and others that follow along these lines (U.S. Pat. Nos. 6,164,002, 6,223,644, 5,852,891, 4,803,910, and 4,685,379), require the firearm to be handled in a manner different from a long-arm style. This, and the extreme dexterity typically required to operate these “trigger assemblies” interfere with the accuracy of the shot.
Thus, there remains a need for a device and method that accelerates the rate of the firing cycle of a semi-automatic firearm that does not interfere with the shooter's handling of the firearm and cause him to miss his target. Additionally, there remains a need for such a device and method that does not require extreme dexterity to operate, and that can be used with most any semi-automatic firearm without substantially and irrevocably modifying the firearm. The present invention addresses these needs.